The operation of cutting a cylindrical hole in a sheet of metal by the punch and die is called
Shearing
Piercing
Punching
Blanking
Correct Answer :
B. Piercing
Related Questions
In a centrifugal casting method
Core is made of sand
Core is made of ferrous metal
Core is made of nonferrous metal
No core is used
The fullers are used
For finishing flat surfaces
For necking down a piece of work
For punching a hole
To finish the punched hole
Loam sand is a mixture of
30% sand and 70% clay
50% sand and 50% clay
70% sand and 30% clay
90% sand and 10% clay
A three high rolling mill consists of three rolls placed one above the other. Which of the following statement is correct?
The upper and middle rolls rotate in the same direction whereas the bottom roll rotates in opposite direction
The upper and bottom rolls rotate in the same direction whereas the middle roll rotates in opposite direction
The bottom and middle roll rotate in the same direction
Any one of the above
In a hot chamber die casting machine
Ferrous alloys with low melting temperature are casted
Ferrous alloys with high melting temperature are casted
Nonferrous alloys with low melting temperature are casted
Nonferrous alloys with high melting temperature are casted
For gas welding, the pressure desired at the welding torch for oxygen is
7 to 103 kN/m²
70 to 280 kN/m²
280 to 560 kN/m²
560 to 840 kN/m²
A casting defect which results in general enlargement of a casting is known as
Shift
Sand wash
Swell
Scab
In a simple die
Two or more operations are performed simultaneously at the single stroke of the ram
Two or more cutting operations are performed at one station of the press in every stroke of the ram
Both cutting and non-cutting operations are performed at one station of the press in every stroke of the ram
None of the above
In a ________, two or more operations are performed simultaneously at the single stroke of the ram.
Simple die
Progressive die
Combination die
Compound die
The upsetting is a process of
Increasing the cross-section of a bar
Reducing the cross-section of a bar
Joining the two surfaces of metal under pressure after heating
Bending of a bar
Cold working of metal increases
Tensile strength
Yield strength
Hardness
All of these
In backhand welding, the angle between the welding torch and the work is kept as
30°-40°
40°-50°
50°-60°
60°-70°
The current in electric resistance welding can be regulated by
Varying the input supply
Changing the primary turns of the transformer
Changing the secondary turns of the transformer
Any one of the above
In a _________, the molten metal is poured and allowed to solidify while the mould is revolving.
Die casting method
Slush casting method
Permanent mould casting method
Centrifugal casting method
A two high rolling mill consists of two rolls which rotate
At the same speed and in the same direction
At the same speed but in opposite direction
At different speeds and in the same direction
At different speeds and in the opposite direction
The shrinkage allowance for cast iron pattern is
10 mm/m
16 mm/m
20 mm/m
26 mm/m
Acetylene gas is stored in cylinders in
Solid form
Gaseous form
Liquid form
Any one of these
In a cold chamber die casting machine, only nonferrous alloys with _________ are casted.
Low melting temperature
High melting temperature
Both (A) and (B)
None of these
If an aluminium pattern made from a wooden master pattern is to be used for grey iron castings, then the shrinkage allowance allowed on the wooden pattern should be
10 mm/m
16 mm/m
20 mm/m
26 mm/m
In a cold chamber die casting machine
Melting pot is separate from the machine
Melting pot is an integral part of the machine
Melting pot may have any location
Low temperature and pressure is used
When a pattern is made in three parts, the ________ is known as a drag.
Bottom part
Middle part
Top part
None of these
The tolerance produced by shell moulding process of casting is
+0.05 mm
±0.2 mm
+0.5 mm
±1 mm
The teeth of hacksaw blade are bent
Towards right
Towards left
Alternately towards right and left and every third or fourth left straight
May be bent in any direction
In a four high rolling mill, the diameter of backing up rolls is ________ the diameter of working rolls.
Equal to
Smaller than
Larger than
None of these
The dowels are
Wooden nails
Box nails
Wire nails
None of these
The temperature produced by oxy-hydrogen flame is about
1800°C
2100°C
2400°C
3200°C
V-block is used to
Check the trueness of flat surfaces
Locate centres of round rods
Check the surface roughness
None of these
Rotary swaging
Is extensively used for making bolts and rivets
Is used for reducing the diameters of round bars and a tube by rotating dies which open and close rapidly on the work
Is used to improve fatigue resistance of the metal by setting up compressive stresses in its surface
Consists of pressing the metal inside a chamber to force it out by high pressure through an orifice which is shaped to provide the desired form of the finished part
In arc welding, the electric arc is produced between the work and the electrode by
Voltage
Flow of current
Contact resistance
All of these
Galvanising is a
Zinc diffusion process
Process of coating zinc by hot dipping
Process used for making thin phosphate coating on steel
None of the above